The more obvious advantages in the use of relatively light weight traction vehicles to perform the functions normally assigned to switching locomotives in railway shops, switching and rail yards are cost savings and, in the case of steerable rubber tired vehicles, maneuverability. Exemplary are the general recognitions contained in U.S. Pat. Nos. 3,198,137; 3,232,241; 3,380,397; 3,427,044 and 3,638,579. Notwithstanding the obvious savings to purchase and maintain such vehicles as compared with conventional switching locomotives, their special design parameters substantially limiting the same to the rail car environment coupled with a relatively low volume requirement yet impose the usual high cost factor of specially designed equipment as compared with the economics of mass production. One such special design parameter relates to achieving the required traction for rail car movement.
The purpose of the invention is to modify a conventional, mass produced over-the-road vehicle whereby the same may be selectively employed for conventional over-the-road or rail car movement.